Assessment and Reduction of Diaphragmatic Tension During Hiatal Hernia Repair

Background: During hiatal hernia repair both axial tension along the esophagus and radial tension on the diaphragmatic hiatus need to be reduced in order to effect a successful repair and hopefully long term resolution. Axial tension is typically and simply assessed by determining the length of intra-abdominal esophagus, and then reduced by mediastinal mobilization and when necessary Collis gastroplasty. There is no similar simple intra operative assessment of radial tension nor is there data that estimates baseline tension or quantifies the effect of induced left pneumothorax or relaxing incisions.

Methods: We assessed the diaphragmatic characteristics and tension of consecutive patients undergoing hiatal hernia repair with a calibrated tension gauge designed specifically for use during laparoscopy. Tension was estimated after complete dissection of the hiatus and mobilization of the esophagus at the point on the diaphragm where when closed it would approximate the size of the esophagus. Tension was then assessed after a deliberate left pleurotomy or partial thickness relaxing incision or both.

Results: A total of 51 patients (23M:28F) underwent laparoscopic hiatal hernia repair. Hernias were classified as type 1 (16 patients), 2 (2 patient), 3 (28 patients), 4 (5 patient). After dissection, the “left to right” size of the hernia was an average of 3.47 cm (2 – 5) and the average baseline tension 16.6 mmHg (8 – 25). There was a linear correlation between size of the hernia and tension on the hiatus.

A relaxing maneuver was not performed in 15 in whom the baseline tension was 10 mm Hg. Relaxing maneurvers were left pleurotomy (18), relaxing incision right crus (14) and both maneuvers (4). Tension was reduced by 35% after a left pleurotomy; where as a right crural relaxing incision reduced tension by 47.8%. When both maneuvers were performed tension was reduced via pleurotomy by 20.8% and an additional 26.3% with the relaxing incision for a total reduction of 41.6%.

Conclusions: Tension on the diaphragmatic hiatus can be measure with a special device introduced via laparoscopy. Diaphragmatic tension appears to be related to the width of the opening of the diaphragmatic hiatus. Relaxing maneuvers such as a left pleurotomy or a right crural relaxing incision lead to reduced tension on the diaphragm. These findings provide objective data on the tension during hiatal closure and may help reduce the incidence of hiatal failure after primary repair.